Chapter 1

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SCIENTIFIC AMERICAN SUPPLEMENT NO. 841

NEW YORK, FEBRUARY 13, 1892

Scientific American Supplement. Vol. XXXIII, No. 841.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.

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TABLE OF CONTENTS.

I. ANTHROPOLOGY.--Investigation of a Mound near Jefferson City, Mo.--By A.S. LOGAN.--Prehistoric remains from the banks of the Missouri River II. BIOLOGY.--New Observations on the Language of Animals.--By M. DE LACAZE DUTHIERS.--A lengthy examination of some facts in the language of animals, including birds and quadrupeds

III. BOTANY.--Electricity in Agriculture.--By CLARENCE D. WARNER.--The effect of currents of electricity upon the germination of seeds. --Interesting experiments detailed, which can be easily repeated

Electricity in Horticulture.--The effect of the electric light on vegetation, availability it may possess for the gardener

Pentapterygium Serpens.--A Himalayan flowering plant introduced in England about ten years ago.--2 illustrations

The Perforation of Flowers.--What insects do to promote the propagation of plants by perforating the flowers in search of honey.--16 illustrations

IV. CHEMISTRY.--A New Laboratory Process for Preparing Hydrobromic Acid.--By G.S. NEWTH.--Simple synthesis of hydrogen and bromium

Boron Salts.--Boron sulphides and selenides and silicon selenide

Detection of Peanut Oil in Olive Oil.--A practical laboratory test for the above adulteration

Hydroxylamine.--Recent preparation of this compound and its properties

New Boron Compounds.--Compounds of boron, phosphorus, and iodine recently prepared by M. MOISSAN

Sapotin, a New Glucoside.--By GUSTAVE MICHAUD.--Preparation of a new glucoside from almonds and other sources

V. CIVIL ENGINEERING.--Completion of the Mersey Tunnel Railway.--The penetration of the bed of the Mersey River by a tunnel at the rate of 150 feet per week.--Details of the work

VI. EDUCATIONAL SCIENCE.--Chinese Competitive Examinations. --Interesting details of the famous examinations of China.--Fatal consequences to overworked competitors

VII. ELECTRICAL ENGINEERING.--High Speed Engine and Dynamo.--A high speed compound engine, running at 500 revolutions per minute, with direct-driven dynamo for electric lighting.--3 illustrations

VIII. MEDICINE.--The Treatment of Rattlesnake Bite by Permanganate of Potassium, Based on Nine Successful Cases.--By AMOS W. BARBER, M.D.--The use of this powerful disinfectant, and the proper treatment and mode of applying it.

IX. METEOROLOGY.--Modification of Our Climate.--By JOSEPH WALLACE.--Climate epochs and the probabilities of the present climatic era.--Changes within the records of man

The Eruption of Krakatoa.--A graphic description of this catastrophe, involving the lives of 35,000 people

X. MILITARY ENGINEERING.--The Military Engineer and His Work.--By Col. W.R. KING.--A Sibley College lecture, treating of the special problems In fortifications, sieges, and the more pacific work of surveys and explorations

XI. MINERALOGY.--Natural Sulphide of Gold.--By T.W.T. ATHERTON.--A probable new occurrence of gold

XII. NATURAL HISTORY.--The Living Jerboa in the Zoological Garden of Berlin.--A rare rodent from South Africa, one seldom seen alive in captivity.--5 illustrations

XIII. NAVAL ENGINEERING.--Twenty-four Knot Steamers.--The possibility of fast ships for long voyages.--The prospects and difficulties

XIV. RAILROAD ENGINEERING.--A Steam Street Railway Motor.--A noiseless motor built of steel on trial in Chicago.--1 illustration

XV. SANITARY ENGINEERING.--Some Means of Purifying Water.--Different filtering processes and the subsidence treatment of water

XVI. TECHNOLOGY.--Action of Caustic Soda on Wood.--By M.H. TAUSS.--Direct experiments on the action of lye on wood at various pressures

Burning Brick with Crude Oil Fuel.--The use of petroleum in brick kilns.--Its advantages, cleanliness, and cheapness.

Chlorine Gas and Soda by the Electrolytic Process.--The decomposition of common salt solution into chlorine and caustic soda on the commercial scale

How Enameled Letters are Made.--The manufacture of separate enameled letters as conducted in London.--5 illustrations

How Mechanical Rubber Goods are Made.--Hose, corrugated matting, packing, and jar rings.--Processes of their production

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THE LIVING JERBOA IN THE ZOOLOGICAL GARDEN OF BERLIN.

Like other strangely formed quadrupeds, the jerboas are counted among the curiosities of the animal kingdom, and as such are described in natural history; but, nevertheless, there has never been a good exhibition of them, for the simple reason that live jerboas are seldom seen in Europe, as they usually die during the journey hither or soon after their arrival. After some hesitation I decided to purchase a pair that I happened to find mentioned in the price list of Mr. C. Reiche, of Alfeld, as one of the most interesting specimens obtained during his expedition to South Africa the year before; but I, also, found the sensitiveness and delicacy of the jerboa very trying, for the short journey from Alfeld to this city caused the death of the female and reduced her mate to such a condition that when it arrived there seemed little hope that it could ever be utilized for scientific research or artistic life studies.

My anticipation and pleasure were changed to vexation and grief. The most careful nursing--the stiff, weak little legs were dipped into and rubbed with French brandy--and a warm pen with a dry sanded floor directly over a heater, did their work. As the new-comer got on his feet again my hope gained new life, and now our jerboa is my delight. It is, indeed, a curious animal. One who saw it only in the day time asleep would scarcely know what he had before him, for he would see little more than a mass of soft, bright sandy hair. The coming of the keeper with the dish of food and the unfastening of the door of the cage bring life to the ball of hair in the corner; a part of it is unrolled and the long, black-tipped tail with two lines of hair is laid out on the ground, and then on each side of it a leg is run out which is nearly as long as the tail and is provided with blunt, smooth, hoof-life nails; and, finally, the head and body are distinguishable and the animal stretches out comfortably on its back in the sand. The fine-skinned, hairless ears still hang limp, the eyes are half closed and the short fore legs are crossed under the chin.

But now the animal gets on its legs by an elastic swing, and its ears are raised and its eyes wide open, so that we can see that the latter are large and dark, with long eyelashes. Then the jerboa raises himself to his full height and playfully measures his cage by one bound from corner to corner. Soon after, the fresh food receives due attention, the animal either jumping toward it in rabbit fashion or crawling slowly on all fours. When it has reached its goal it again assumes the upright position, in which it is evidently most comfortable, and begins to eat it in his own peculiar way; that is, sitting on his hind legs he quickly seizes a piece of bread, turnip or other food in his fore paws and conveys it to his mouth, apparently indifferent to the nature of the food before him. He never takes anything directly in his mouth; even the grass on a piece of turf that I had given to him as an experiment was not eaten as it would have been eaten by other animals, but was first plucked with the fore paws. If we notice the position of the mouth, far back on the under side of the head, we will understand that the jerboa could not take his food in any other way. Besides this, nothing of special interest has been observed in this nocturnal creature, but he, of course, lives more regularly and quietly than if his mate had lived.

One who knows anything about the structure of animals' bodies need not be told that the jerboa is a rodent. One glance at the peculiar shape of his head would assure him of that. The form of the rest of its body, especially its long hind and short fore legs, give unmistakable proof that it is related to the jumping rodents; it belongs, in a wide sense, to the family of the jumping mouse, the scientific name (Dipodidea, two-footed) of which is very significant, as the very short fore legs are usually carried close under the chin and are scarcely noticeable when the animal is in its normal position, and are of little use when it moves about. The hind legs are very strong, and when going at full speed the jerboa takes jumps that measure from eight to ten yards, according to the unanimous testimony of various witnesses.

The jumping mouse of North America, which is somewhat larger than an ordinary mouse, is, according to Brehm, also as swift as an arrow or a low-flying bird. This exceptional velocity is not all that reminds us of a bird, for there is also a strong resemblance in the formation of certain parts of the bodies of the two creatures; but, after consideration, this should not seem strange, because in animal organisms similar means are employed to accomplish similar ends. It is only natural that there should be peculiarities in the construction of the limbs and skulls of the Dipodidea with their bird-like movements and bird-like sharp-sightedness, that are usually found only among birds. The consistency between the construction of their bodies and their mode of life is a beautiful example of fitness; only by extraordinary quickness of movement and sagacity could the little defenseless plant-eaters maintain the struggle for existence in the barren steppes and deserts. The formation of the bodies of the different members of the family varies according to their needs. The jerboa is the largest member of the family. Very little is known of his life when free; it being known only that the jerboas are widely spread over the whole of southern Africa, and are nocturnal burrowers of the steppes. During the rainy season they remain in a sort of winter sleep.--_Dr. L. Heck, in the Illustrirte Zeitung_.

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NEW OBSERVATIONS ON THE LANGUAGE OF ANIMALS.

By M. DE LACAZE DUTHIERS, of the Institute of France.

I had occasion in a note published several years ago in the _Revue Scientifique_ to mention a parroquet which I have since continued to observe, the manifestations of whose intelligence are both interesting and instructive. Many acts of birds are difficult of interpretation. To speak only of their songs, the meanings of most of the innumerable varieties of sounds which they produce, and of their diverse warblings, escape us completely. It is not possible to find the meaning of these things except by forming suppositions and hypotheses, or by catching the connections between cries and acts. But instances of the latter kind are extremely rare in comparison with the great majority of the manifestations made by animals.

Thus, to select examples which every one can observe, when a canary bird is warbling in its cage and becomes deafening, or when a lark rises straight up in the air and _incantat suum tirile tirile_--sings its _tirile tirile_--as Linnæus picturesquely expresses it; when a tomtit, leaping from branch to branch of a willow or among the reeds, repeats its florid warblings; when a raven croaks; when a blackbird whistles--what significance can we attach to their songs and their cries? Certainty is impossible, and we can only form more or less plausible hypotheses concerning the interpretation of them.

The parrot furnishes us one more aid in this matter than other birds, and this helps us, to a certain extent, in overcoming the difficulty of interpretation. It has an articulate voice, and when we have taught it a few words, the meaning which it gives them may be better divined by us according to the tone and the rapidity or slowness of its utterance. This permits us to discover the feelings that move it, for we can better judge from an articulate sound than from one that is merely musical.

Much has been written on the language of animals. It is neither my desire nor my intention to repeat here all that may have been said on this subject. It would take too long and would be of no use. I have often witnessed facts that may be of interest to those who are occupied with the mental manifestations of animals. I will simply relate them; and of such as are already known, I will merely mention them anew, admitting in advance a priority for others which I do not demand for myself.

There can be no doubt that animals communicate their impressions by an inarticulate voice. Common sense and the most superficial observations are opposed to the negative of this proposition. But when a canary bird warbles till it stuns us, or a nightingale sings in the shadows on the fine nights of June, can we follow and discover the significance of those modulations--now sharply cadenced, now slowly drawn out, and ending with a trill long and accurate enough to challenge the most skillful musician?

All the poets of every country have constantly sung of the songs of Philomela. But their fervent and enthusiastic verses cast little light on the value of the nightingale's song. It is said that the male sings for the entertainment of the sitting female, but there is no proof of the assertion. The note warning of the approach of danger is easier to recognize. The bird utters a short, hoarse cry, and repeats it with a succession of _trrre, trrre_, which is impossible to mistake. When we hear this cry we may be sure that an enemy is near. Music gives way to a cry of distress and warning, and the female leaves her nest if the sounds become piercing. What do we know of the gobbling of the turkey, which the whistling and the cries of children excite? They are doubtless responses to those challenges; but what do they mean?

The crowing of the cock, recurring regularly at fixed hours, has some signification, but we cannot comprehend it. If on a fine afternoon in autumn the cock crows, and repeats his strain between two and four o'clock, the countrymen in some places will say there will be a fog on the morrow, and they are generally not mistaken. Hens do not mistake his notes either; when a leader of the troop, coming upon a spot rich in food, utters his peculiar chuckle, they run from all around to share the find with him. It is evident that the cock has called them and they have understood him. These facts indicate that there is some definite sense in this inarticulate language; and examples of it, taken from other groups, might be multiplied.

The dog, intelligent animal as he is, manifests his affection on meeting his master, with peculiar cries which vary with the intensity of his joy. No one could confound these notes of pleasure with those which he utters when he is angrily driving away a beggar, or when he meets another dog of unpleasant appearance and puts himself in the position of attack.

An interesting study of the voice of the dog on guard may be made in the country at night. If another dog barks in the distance, the house dog answers in a peculiar manner. He gives a few growls, stops, seems to listen, begins again, very often getting answers; and, after two or three interruptions, he terminates his barking with abrupt yelps, loud at the beginning and long drawn out, and gradually dying away. This ending of his cries is habitually accompanied by his raising his head and throwing it back. I have often, when within the house, on hearing the watch dog bark in this way, opened the window to assure myself on the subject, and distinguished, as I could not do with the windows closed, the voice of another watch dog barking in the same way in the distance--the barkings of the two dogs alternating, one answering the other. There is in such cases an evident communication of impressions. One of the dogs, having had his attention aroused by some unusual noise, has transmitted his impression to the other, as sentinels posted at intervals call out theft warnings one to another. I have often repeated this observation during the long evenings of winter.

Another example, little known in thickly populated countries, is drawn from a curious scene which I witnessed during a winter passed in Perigord Noir. We had remarked that for several nights the three watch dogs, a young and an old male and a bitch, howled often toward midnight, but in a peculiar way. One night in particular, during their tedious concert, just as we had got to sleep, they mingled with their cries howlings like those they would have uttered if they had been beaten, with a shading hard to define, but which we perceived plainly; and we remarked that, leaving their kennel in the avenue that led up to the lodge, they had come to close quarters with one another at the gate, with alternating howlings and plaintive cries. Inquiring in the morning for the cause of these singular cries, the peasants told me that a wolf had passed, and predicted that it would return. They said, too, that a neighbor's hunting bitch had disappeared, and its bones had been found in the fields near a wood. We were awakened again about midnight by the cries of the dogs, and the scene was renewed. Informed as we now were of the nature of what was going on, we ran to one of the windows, whence we could see, in the clear light of the moon, all that passed. The three dogs were cowering against the gate, the oldest one howling by the side of the others, while the younger one and the bitch were exposed at intervals to the attacks of another animal, browner than they, and of about their size, without defending themselves, but moaning as if they were undergoing a vigorous correction.

Frightened, doubtless, by the opening of the blinds of the first story above him, the strange animal had gone away and was sitting in the middle of the road. We could only see that he had straight ears. While we were going down to get a gun the visitor came back to his charge on the dogs, which had begun howling after he left them, and resumed the cries significant of chastisement when they were attacked again. For some reason, perhaps because he heard the click of the gun, the foe drew back and sat down in a garden walk, concealed by a bunch of shrubbery. The three dogs, notwithstanding our reiterated urging, were no more disposed to pursue him than before. If the assailant had been a dog they would have rushed upon him, but they stayed cowering at the gate and howled distressfully. The bitch was most affected, and they all seemed paralyzed by fear. It is said in the country that bitches are especially liable to be attacked by wolves. It was so here. The most certain feature in the matter was the terror of the animals. They were capable of resisting the attack three times over. The young dog was a savage one, and passers-by were afraid of the bitch; but that night they were terrorized, and all incapable of defending themselves. Their cries were therefore due to the same cause as in the preceding night--the presence and attacks of the wolf. I could not have realized their meaning if I had not been a witness of the scene--that is, I could not have correlated the cries and the acts.

A shot at the animal behind the bushes was followed by a hoarse cry. He was hit, and ran; but, in spite of our urgings, the dogs stayed at the gate and only stopped howling. Under any other conditions, upon the signal of the shot they would all have started in pursuit of the wounded animal.

A wolf came to the farm during the last winter (1890-91) and attacked the same bitch. He would have carried her off, for he had seized her by the throat, if we could judge from the stifled cries she uttered; but this time he found with her a new watch dog--a mountain bitch from the Pyrenees--of a breed that attacks the wolf and the bear. The wolf would have been caught if he had not run away. He did not return, for he had been attacked, and learned what he had to deal with.

The Pyrenean breed furnishes excellent watch dogs. I knew one of remarkable traits. At evening he would go round the house, giving two or three growls at each door. With his head raised he seemed to listen to his fine voice, then he would start again and go to another door. He seemed desirous to show those who were observing him that he was attending to his post as guardian. He then went away in silence along the walk, through a dark, rising hedgerow, leaping the slight hillock, yelping toward the wood. He listened, yelped again, and went in. There was never any failure in this performance, but every evening as night was coming on he began his round, which no one had taught him. It was all done in his function as a guard. It would be hard to determine what his yelps meant, but there were in them an inflection, a sonorousness, and a continuance quite different from those he uttered when pursuing a passer-by or when going to meet a person coming toward the house. Every one who has a watch dog is able to tell by the sound of his barking when a person is coming up, and usually what sort of a visitor it is.

The peasants' dogs of the southwest of France dislike the country millers, because of the long whips which they are always carrying and snapping, and with which the dogs, running after them, are often struck. From as far off as the snapping of the whip can be heard, the dogs come to wait for the millers and pursue them; and it is easy to recognize when the millers are passing, by the behavior of the dogs. There is in this also a significance, at once aggressive and defensive, in the cries which one can, by giving a little attention, soon learn to distinguish.

Another example of the reality of the various meanings of the cries of the dog under different circumstances is afforded by the companies that collect around a female in heat.